Children's clothing

We wouldn't recommend going the used route on important items like car seats or strollers, but when it comes to children's clothing — which they'll grow out of quickly and is likely to get wrecked by smashed carrots anyway — there's no shame in saving.

Toys for your tots

Do your budget a favor and skip Toys "R" Us for these more affordable used-goods options: Craigslist, eBay, Swap.com, or neighborhood yard sales.

Each is a gold mine when it comes to finding cheap, but still usable, cast-off toys.

Furniture

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Reseller sites like Craigslist are treasure troves for anyone looking for used furniture. And if you're not willing to put up with flaky sellers or bed-bug threats, don't be afraid to ask family and friends to see if they're looking to get rid of any furniture.

For brides-to-be on a budget, check out the virtual racks in Tradesy's wedding section to score discount gowns and accessories that no one will ever guess were used. For grooms and groomsmen, shop for a secondhand tux and use the money you saved for tailoring.

And remember, you can resell the garments you only wear once — just be kind to them so you'll get as much of their value back as possible.

Fitness equipment

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Whether you're a fitness nut or just getting into exercise, buying brand-new equipment is unnecessary. Most gym equipment, such as dumbbells, medicine balls, and ladders, doesn't have an expiration date.

Plus, if you don't end up using the elliptical or weights as much as you'd planned, you won't feel as guilty about the purchase later on.

If you're looking to invest in big-ticket items, such as a treadmill or other exercise machines, you'll want to put in a good amount of research and scrutinize the products more. Play It Again Sports sells used equipment at various store locations, and eBay and Amazon have a variety of offerings.

Tools and gardening supplies

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Stocking up on brand-new tools isn't worth it, especially if you won't be using them consistently. Tools have a long lifespan, and chances are, the used screwdriver or hammer you find at a garage sale or on Craigslist will last you forever.

If you're looking to invest in power tools, you should be more diligent when picking out used ones. Start by visiting the websites for Sears, The Home Depot, Lowe's, or Ace Hardware to get an idea of prices and models (visit the store if you can so you can actually pick up the tools).

Then look at sites like eBay and Craigslist. Pay attention to the age and condition of the tools described when comparing prices.

Pawnshops, thrift stores, live auctions, flea markets, and garage sales are also good places to score a deal on used tools.

Instruments

If you're in the market for a new hobby or want your kids to get involved in music, don't bother dropping hundreds on a new instrument, especially if you're not sure you or your kids will continue with it after a year or two.

Check out Craigslist or eBay for some steals. There are even secondhand stores and websites that sell instruments exclusively, like Music Go Round and Guitar Center.